I agree, but the question is for how long. I think your belief that it would have been no more than a decade is unrealistic. Having fought a war expressly for the defense of slavery and including clauses in their constitution expressly forbidding the outlawing of slavery, it seems highly unlikely that just a few years later they'd ban the peculiar institution.
While it's possible that some slaveowners would have individually seen the economic sense of emancipation and freed their slaves, I think slavery as a legal institution would have survived well into the 20th Century. Keep in mind that mechanization and advances in pesticides didn't reduce the need for intense labor on cotton until the 1940s.
If you listen to the “Lost Causers or their sympathizers slavery was already a ‘’dying institution’’ in 1861.(hogwash!) The moral and social imperative against it would have demanded it’s end. And blacks themselves certainly would have rebelled, perhaps more successfully than other failed attempts. Maybe not in a decade perhaps but I would think certainly by the mid-1870s.